Art of manufacturing saws



' (No Model.)

v 0. PROUTY. ART OF MANUFACTURING SAWS.

No.46 1,509. Patented Oct. 20, 1891.

UNITED STATES PATENT meal CHESTER PROUTY, OF BIG RUN, PENNSYLVANIA.

ART OF MANUFACTURING SAWS.

SPECIFICATION forming part of Letters Patent No. 461,509, dated October20, 1891.

Application filed April 28, 1891. Serial No.390,'746. (No modeLl T aZZwhom it may concern:

Be it known that I, CHESTER PROUTY, a citizen of the United States,residingat BigRun, in the county of Jefferson and State of Pennsylvania,have invented certain new and useful Improvements in theArt ofManufacturing Saws; and I do hereby declare the following ance with myinvention.

to be a full, clear, and exact description of the invention, such aswill enable others skilled in the art to which it appertains to make anduse the same.

My presentinvention relates to an improvement in the art ofmanufacturing crosscutsaw blades; and the objects are, first, to producean improved saw which will not pinch in the kerf; second, to provide animproved raker-tooth to lift the sawdust out from the bottom of the kerfand discharge it at each stroke, and, third, to improve the manufactureof the raker-teeth in the first-qu alitysaws.

My invention consists in the manufacture of orosscut-saws, which will behereinafter fully described, and particularly pointed out in the claims.

To enable others to understand my invention, I have illustrated the samein the accompanying drawings, in which Figure I is aside view of anembryonic sawblade, showing one method of grinding the blade. twobevels. Fig. III is a side view of a corn pleted or finished sawconstructed in accord- Figs. IV and V are transverse sectional views onthe lines :1: 0c

and y y of Figs. I and II, respectively. Figs.

VI and VII are enlarged detail views of cutter and raker teeth,respectively; and Figs. VIII and IX are detail views of the swagc.

Referring to the drawings, in which like letters of reference denotecorresponding'parts in all the figures, A designates the blank of asawblade, which blank is made of the best tempered steel and is curvedlongitudinally, so that the upper edge or back a is concaved and thelower or cutting edge ct is convex. The convex edge a of the blade orblank has the teeth formed thereon, as will be more fully describedhereinafter, in a line substantially concentric or parallel with theconcaved back. Thus the'cutting-edge a is curved, and at the center-theblade is wider than it is at the ends; but the cutting and raking teethare all of the Fig. II shows another method withsame depth andthickness, and there are-the usual small teeth B at the ends of theblade. It has been found by practical use that the ordinary taperingwhich is given to the saw-' blade is not sufficient to reduce it'to auniform gage throughout its length nor to'secure a properdegree ofsmoothness 011 its surfaces, and in some instances the saw-blade hasbeen partially ground, the grind extending from the base of the teeth tothe back of the blade, to produce the desired gage; but I have found itvery desirable that the lower part of the saw-blade, on which the teethare formed, should also be ground, and the results thereby obtained arehighly beneficial and useful in a device of the kind to which thisinvention relates.

As indicated in Figs. I and IV, the blank or plate is cut, teeth andall, out of a sheet of the best steel and tempered and ground throughoutfrom end to end, the grinds extending in parallel curved lines from theback edges to a line beginning at the small teeth at the ends of theblade and extending throughout the entire length of the saw-blade saidblade and 19 gage in the center, where the blade is somewhat wider.

The grinding and the beveling of the blade,

as herein shown and described, enable me to produce a saw having manyadvantages over prior devices, as the saw-blade will not bend or hang inthe kerf, thus obviating the common defect in other saws, which havetheir effectiveness impaired and easy practical sawing renderedimpossible by binding in the kerf and the inability to rapidly andthoroughly carry off the sawdust.

I11 Fig. II I have shown another method of' grinding the saw-blade,which consists,.essentially,i11 first grinding that portion of the bladein which the teeth are formed and then grinding the other portion onbeveled lines, the bevel of the latter grind-being slightly greater thanthe former, as shown in Figs. II

and in practicing this latter method I have the saw-blade made of thebest steel, as

before described, and then temper it in the.

usual manner, the teeth and general contour of the saw being stamped outin embryo. The blade is then ground from end to end in curved linesparallel with the back edge, and the bevel of the grind extends from thecutting-edge a to a line drawn parallel with the back edge a aboutmidway between the cutting and back edges. This bevel leaves the gage atthe ends of the main teeth about 14:, and near the ends it diminishes to14:1, and the bevel at the other end of the grind is about 15%, thusleaving a gradually-diminisl1ing bevel from the points of the teeth tothe center of the blade. The other bevel begins where the first bevelterminates-about the longitudinal center of the blade-and for thepurpose of better illustrating these bevels I have shown the first insolid curved lines and the second in dotted lines. The second grindingis substantially similar to the other, as it runs from end to end of theblade in regular curved lines parallel with the curved back edge a ofthe saw, and the bevel diminishes grad ually from 15:} gage, where itadjoins the first bevel, to about 18 gage at or near the ends and about19 gage in the center, where the blade is widest. These two grindsproducea blade with a bevel of from ll and 14:} gage to 15-1; gage,extending from the points of the teeth back to a median line parallelwith the curved back edge a, about the center of the saw, and anotherbevel of from 151}- gage to 18 and 19 gage, adjoining the first beveland extend ing to the back of the blade. This improved method ofgrinding produces a sawblade which will not pinch in the kerf and givesa blade with a graduallydiminishing thickness from the points of theteeth to the back edge a, which will wear uniformly in gage at allpoints instead of wearing out of gage, as with ordinary saws. The bevelsare substantially those which should be used on all saws; but as theblades used for different purposes vary considerably the bevels mustalso vary proportionally.

In order to overcome the disadvantages arising from continuallyrecutting sawdust which is not removed from the kerf, I provide improvedraker-teeth, by which the sawdust is removed from the kerf ateach'stroke of the saw, which teeth are shown in Figs. VI and VII,respectively.

The cutter-teetl1 O are provided with doublecutti'ng pointed teeth 0,separated by a circlecrotch c, and they are set and ground to suitdiiferent styles of saws to saw different kinds of timber. The raker orcleaning-tooth D is also double pointed, and the ends of each point doverhang the opposite cutter-tooth, respectively, and the gumming cl ofthese teeth extends nearly half way down the raker. These rakers can bemade in half-form or cut to plate in any way to produce the same eitect,and as the gumming div-ides the two points of the raker they requireless filing to keep them in order, and at each stroke of the saw therakers take up the sawdust and discharge it. The small teeth B at eitherend of the saw are to be properly regulated, so the large teeth will bedistributed correctly. They may vary from three to eight teeth, ifrequired; but I prefer to have five at each end, and they are to be cutdeeper than in ordinary saws, and the adjoining teeth are to be cutrounding with that of the rakers and tiled beveling, and this bevel isto run aboutone-fourth of an inch back on both edges of eachcutting-tooth, thus bringing it to a point, and every other tooth of thesaw is to be provided with this bevel. The raker-teeth D are to be cut atrifle shorter than the adjoining cutting-teeth and are to be filedsharp from the inside, so as to let them strike the wood as a plane andcut away the wood instead of tearing through it, as in the ordinaryraker-teeth. The cuttingteeth 0 are to be set to suit the kind of timberto be cut, and they are pointed and have a true bevel on each side ofthe point, as hereinbefore stated, and the grinding of the blade makesthe saw true along the entire edge, or nearly so, thus giving it atendency to wear in gage instead of out of gage, and cuts faster andtruer than the ordinary saw until it is worn out. These saws are to bemade of the best steel plate and are to be properly tempered beforefinishing. The teeth can be cut by dies of any improved style in commonuse, so as to punch out the desired sizes and shapes; but in thefirst-quality saws I prefer to make the rakers temper-drawn, so thatthey.

can be svvaged with the swage E. (Shown in Figs. VIII and IX.) Thisswage is tapered slightly toward its point e, and one half of itsperiphery I is curved substantially concentrio with the center, and theother half has two angularly-disposed sides fmeeting at a point in aline with the center of the tool. These sides f, while substantiallystraight, also have aslight longitudinal taper. The square parts of theswage are to be placed against the square edges of the cutting-teeth,and the round curvedside of the swage is of the proper form to give theraking-teeth any desired overhang. be given to the raking -teeth byusing this swage by changing its position. Vhen in the desired position,where the teeth are to be bent, the swage is held firm and struck with ahammer, which will thus bring the rak'er to the proper shape. Thisswaging can be carried on until the saws are worn out. This swagingprocess can be done with the sawblade at an ordinary temper; but in themore costly saws of the first class I prefer to retemper the raker-teethto prepare them for heavy swaging, which result can be accomplished bydrawing the raker-teeth individually with hot tongs. To temper therakerteeth separately from the cutting-teeth, the rakers can be heatedby gas-j ets or perforated pipes and gas-light burning against orbelow Anumber of difiierent bevels can IIS one or more of the raking-teeth andnot permit the cutter-teeth to be exposed to the heat. This processrenders all the raking-teeth of uniform temper and willgive them aproper temper forthe continued or repeated process of swaging; but inordinary saws this is not necessary, as the raking-teeth are filednarrower than on other saws and can be swaged when of uniform temperwith the cuttingteeth, which latter teeth have a proper temper forsetting.

Having thus fully described my invention, what I claim as new, anddesire to secure by Letters Patent, is-

1. The improvement in the art of manufacturing a crosscut-saw, whichconsists in grinding a saw blade from end to end in curved linesparallel with the back concaved edge of the saw-blade, said grindextending from the points of the teeth to the longitudinal center ormedian line of the saw-blade, substantially as described.

2. The improvement in the art of manufacturing crosscut-saw blades,which consists in grinding the plate from end to end in parallel linesextending from the points of the teeth to the longitudinal center of theblade and then again grinding the blade in beveled longitudinal linesextending from the terminus of the first grinding to the back edge ofthe blade, substantially as described.

3. The improvementin the art of manufacturing crosscut-saws, whichconsists in grinding the plate with two bcvels extending from end to endin curved lines parallel with the back edge thereof, substantiallyasdescribed.

4. The improvementin the art of manufacturing crosscut-saw blades, whichconsists in twice grinding the blade from end to end in curved linesparallel with the back edge thereof, the first grinding having abevel'extending from the points of the teeth to the median line of theblade and the second grinding being on a greater bevel extending fromthe terminus of the first grinding to the back edge of the blade,substantially as described.

5. The improvement in the art of manufacturing crosscut-saw blades,which consists in tempering and drawing the raker-teeth independently ofor separately from the cuttingteeth, substantially as described.

6. The improvement in the art of manufacturing crosscut-saws, whichconsists in stamp-. ing the blade out of a piece of metal, tempering theblade and forming the teeth thereon, grinding the blade, thenretempering and drawing the raker-teeth, and finally finishing the bladeand teeth, substantially as described.

7. A crosscut-saw blade stamped from a piece of metal and having itsraker-teeth tempered and drawn separately from the cuttingteeth,substantially as described.

8. A crosscut-saw blade stamped from a piece of tempered steel andhaving its rakerteeth tempered and drawn independently of thecutting-teeth and swaged to give the desired overhang to saidraker-teeth, substantially as described. I

9. The improvement in the art of manufacturing crosscut-saw blades,which consists in stamping the embryonic blade out of a sheet oftempered steel and forming the raker and cutting teeth thereon,subjecting the rakerteeth to the action of heat without affecting thecuttingteeth, drawing out the raker-teeth, and then swaging saidraker-teeth to give the same the desired overhang, substantially asdescribed.

10. In the manufacture of crosscut saw blades, a swage for forming theraker-teeth, having a segmental surface and the angular sides,substantially as and for the purpose described.

11. In the manufacture of crosscut saw blades, a longitudinal taperedswage having a rounded side substantially concentric with its axis andthe two straight sides arranged in an obtuse angle to each other,substantially as described.

12. A crosscut-saw blade ground in longitudinal parallel curved lineswith two bevels of different gages and having its raker-teeth retemperedand drawn, substantially as described.

In testimony whereof I affix my signature in presence of two witnesses.

CHESTER PROUTY.

Witnesses:

THOS. H. SIMON, J NO. J BREFALL.

